1. Technical Field
The present invention relates to a semiconductor device that consolidates a high-frequency circuit and a digital circuit.
2. Related Art
In recent years, as miniaturization of CMOS transistors has advanced, it has been possible to obtain characteristics where a current gain cut-off frequency f exceeds 100 GHz. To this end, for example, CMOS transistors have been used in place of compound transistors and bipolar transistors as transistors constituting high-frequency circuits for carrying out wireless communication etc. (for example, refer to patent documents Japanese translation of PCT international NO. 2008-503892, Japanese Laid-Open patent publication NO. 2008-85117, 2006-100824 and 2005-228906). It is therefore possible to consolidate digital circuits and high-frequency circuits on a single semiconductor chip when it becomes possible to make high-frequency circuits using CMOS transistors. It is therefore possible to put manufacturing know-how accumulated as a result of manufacturing of semiconductor devices constructed from digital circuits to use.